Thread-protecting device for embroidering-machines.



MQSGHOENPELD. THREAD PROTECTING DEVIGBFOR EMBROIDERING MACHINES.

' APPLICATION FILED JUNE13, 1910. 1,012, 104.

Patented Dec. 19, 1911.

2 SHEETSSHEET 1.

COLUMBIA PLANOGRAPH couwAsmNa'roN, D. c

M. SCHOENPELD. v THREAD PROTECTING DEVICE FOR EMBROIDERING MACHINES.

APPLICATION I' ILED JUNE 13, 1910.

Patented Dec. 19, 1911.

2 SHEETS-SHEIT 2.

I", COLUMBIA PLANOGIAPH C(L. WASHINGTON. D. C.

MORRIS SCI-IOENFELlD, OF RORSCHACH, SWITZERLAND.

THREAD-PROTECTING DEVICE FOR EMBROIDERING-MAGHINES.

Specification of Letters Patent.

Patented Dec. 19, 1911.

Application filed June 13, 1910. Serial No. 566,499.

To all whom it may concern:

Be it known that I, MORRIS SOHOENFELD, a citizen of the United States, and a resident of Rorschach, in the Canton of St. Gall, Switzerland, have invented certain new and useful Improvements in Thread- Protecting Devices for Embroidering-Machines, set forth in the annexed specification. 4

The subject matter of the present invention is a device for determining when one or more threads of an embroidering machine becomes broken or unduly slack.

In embroidering machines employing a large number of needles and a corresponding number of sewing threads it is diflicult for the operator to properly watch the many threads to determine the moment when any of the threads become broken or so unduly slack that the stitching will be affected thereby and unless the defect is corrected without delay the part of the design being worked by the particular thread or threads which become broken will be defective and the saine must be corrected by hand work when the fabric is removed from the machine, as otherwise the same will not be marketable. This hand work is one of the serious drawbacks in the working of the machine and it is the object of my invention to provide means for immediately detecting whenever a thread becomes broken and which will inform the operator when such occurs so that the defect may be remedied without a material delay.

The present invention relates more particularly to the device which engages the sewing threads for detecting the break in the threads, and it is adapted to be used. to give a visible signal or the same can be used in connection with a stop mechanism for stopping the machine, though this is of doubtful value as in such case the machine is stopped when a break occurs, whereas in many instances the broken or slack threads can be remedied without stopping the machine and thereby delaying the work.

Thread detecting devices have been invented heretofore, but in most cases they have been electrical, that is, operating through an electrical device upon the breaking of a thread to close a circuit and give the alarm. Such devices, owing to the great number of parts are complicated and uncertain. Other devices have been entirely mechanical but in all the elements which engage the threads and perform the function of detecting the defect have been complicated, requiring a large number of parts. In the present invention I have provided a detecting device in which the elements for detecting the defect in the threads are materially reduced in number by making one detecting element engage several threads in such a way that the device will detect a defect in any or all of the particular threads with which it engages, thus making one element or set of elements guard two or more threads and do the work of several sets of mechanisms of prior devices. The present device is simple in its parts and operation and takes up but little space on the embroidering machine.

In the drawings forming a part of this application, Figure 1 is a diagrammatic view illustrating an embroidering machine with my improved detecting device built thereon, Figs. 2 and 2 are elevations of the preferred form of my invention, showing the detecting elements in different positions which they assume during their operation.

In the present showing I have simply nism but I have indicated at 2 the point p where the various sewing threads of the machine are presented during their normal operation.

Under the various threads 2 and longitudinally of the machine I have arranged a bar 3, which is displaceable longitudinally, and this bar carries the operating parts of the detecting mechanism, at least it carries the parts which directly engage the sewing threads. Upon this bar are carried a number of elements which engage the threads lightly and which elements engage each with two or more of the several threads in such a way that if any one of the several threads with which it engages becomes broken or unduly slack, the engaging element will have such a movement as will that particular detecting element engages. By making each detecting element guard two or more of the threads the number of parts may be materially reduced, but the device must be capable of detecting the threads individually.

For contacting with the sewing threads I have provided a plurality of arms or detectors l, which are so located and formed that they each contact with a plurality of the threads 2. shown engaging two of the threads at a time, while they are adapted when reciprocated with the bar 3 to engage others. That is, I have shown one engaging element adapted for protecting three or more threads. This number may be two or more, but I find the device of the present showing quite satisfactory. The arm a is fulcrumed at 5 to the bar 3, which latter carries it, and it extends beyond the fulcrum, where it is provided with a claw 12. On the bar 8 there are also provided elements which are adapted to keep the arms 1 in engagement with their respective threads during the normal position of the latter but which will disengage from the arms l; when an abnormal condition exists, whereby the signal will be given to the operator. This element in the present showing consists of a lever or arm 6, which fulcrums at '7 from the bar 3 and it is provided with a slight weight 8, which is adjustable along a portion of the arm 6 for the purpose of increasing or decreasing the counterbalancing force of the arm 6 on the detecting elements 4. The arms 6 each carry a pawl 9 which fulcrums on the pin 10 of the arm 6, and the movement of which is limited by the pin 11 also carried on a part of the arm 6. These pawls 9 engage in the claw 12 of the element 4 as shown in the left of Fig. 2. It will be noted that the arms a curve upwardly until they reach the plane of the several threads 2 and then they run parallel with such plane and again point downwardly. The arms 1 engage at least two threads all the time and the pressure of the arm 4 is such as will be resisted by two threads.

The mechanism for operating to reciprocate the bar 3 at each stitching operation of the embroidering machine I have shown disposed principally at the ends of the machine. This consists of a coupling 13 which unites the bar 3 with a strap or band 14:, which latter engages aroundthe periphery of a drum 16 mounted on a shaft 19 at one end of the machine. The shaft 19 has a gear 20 thereon by which the drum 16 is revolved by engagement of the gear 21 which is mounted below the drum on a shaft 22. I have shown a rack bar 23 mounted in brackets 241 on the machine which is adapted to be reciprocated up and down and the teeth of which engage the teeth of the gear 21, by

The elements 1 are herewhich the latter is operated. The lower end of the rack bar 23 is provided with a fulcrum block 28 that engages in the slot 26 of a bellcrank lever 25 and by which the rack bar is reciprocated. The bellcrank lever fulcrums on a shaft 26 and its other arm is provided with the well known crescentbowl 29 that engages in the groove 30 of the cam 31 on the main shaft 32 of the embroidering machine, and by means of the cam action the bellcrank lever is operated at each stitching operation of the machine and the movement is transmitted by the rack and gears to the bar 3. The other end of the bar or bars 8 is provided with a strap or band 15 which passes over the idler 17 and the free end is provided with a counterbalancing weight 18 which tends to pull the bars 3 to the left and thereby to return the bars 3 after they have been drawn to the right by the action of the cam.

The operation of the device is simple. When the threads are all under proper tension the detecting elements are in the position shown in Fig. 2 to the left, with the part X of the arms 4. lying against the several threads 2. In this position the pawls 9 engage in the claws 12 and the slight pressure caused by the weight 8 retains the arms at in contact with the threads. So long as the threads are in proper condition the parts will remain in this condition. The bar 3 will be reciprocated at each stitching operation of the machine, when the part X of the arms 4- will move and will contact wit-h more than one of the several threads. If, in the position shown in Fig. 2, to the left, the arms 1 engage two of the threads at one time, they will be made to engage one or more of the other threads in their reciproeating movement and thus detect defects in more than one of the threads. Should any of the threads become broken or unduly slack, so that the work being done by that particular thread would be defective, then the arm a by reason of the slight upward pressure caused by the weight 8, will not be overcome by the threads and as a result the arm 4: will move upwardly as shown in the left hand example of Fig. 2 and right hand of Fig. 2 and the claw 12 of this arm will move until the pawl 9 passes it, when the arm 41, by reason of the greater part of its weight lying to the right of its fulcrum 5, will swing down to the position shown in the right example of Fig. 2. In this position the arm serves to visibly indicate that a defect exists in the threads with which this particular arm engages and the operator can obviate the difliculty. The arm at may be employed to operate a stop mechanism for stopping the embroidering machine, but my present invention relates more particularly to the detecting means.

I have carefully described the details of the preferred form of my invention but it is understood that changes may be made without departing from the scope of my in vention and the annexed claims.

Having described my invention what I claim is;

l. A thread testing device embodying a thread engaging element adapted to engage a sewing thread, and means whereby the thread engaging element will indicate an abnormal condition in the thread, such as a slack or broken thread, said thread engaging element being adapted to detect and indicate a defective condition in any of the threads with which it engages, and means for moving said engaging element to cause itto successively engage and test a plurality of threads.

2. A thread testing device embodying a thread engaging element adapted to simultaneously engage a plurality of sewing threads, and means whereby the thread engaging element will indicate an abnormal condition in a thread, such as a slack or broken thread, said thread engaging element being adapted to detect and indicate a defective condition in any of the threads with which it engages, and means for moving said engaging element across the threads to cause it to successively engage and test a plurality of threads.

3. A thread testing device embodying a movable longitudinally disposed carrying element, a plurality of thread engaging elements carried by the longitudinal carrying element, means whereby the thread engaging elements will indicate an abnormal condi tion of the threads, and means for operating the said carrying element to cause each of the thread engaging elements to successively engage and test a plurality of threads, said thread engaging elements each being adapted to indicate a defect in any of the threads with which they engage.

i. A thread testing device, comprising a support, a movable thread testing element adapted to engage and test a plurality of threads, means for moving the support to cause the said testing element to engage a plurality of threads, means engaging the thread testing element and adapted to support the thread testing element in contact with the threads, said thread testing element being adapted to move upon the break- Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

ing of any of the threads with which it engages, suflicient to cause it to be deprived of the supporting action of the supporting element.

5. A thread testing device, comprising a longitudinal supporting member, a plurality of thread engaging arms fulcrumed on the supporting member and adapted to press the sewing thread, gravity elements engaging the thread engaging elements and retaining them in contact with their threads, said thread engaging elements being adapted to disengage from the gravity elements upon being deprived of the resistance of their threads and means for moving the said supporting member to cause the several thread engaging elements to engage a plurality of threads.

6. A thread testing device comprising a longitudinal reciprocatable bar, thread testing arms fulcrumed to the said bar and having upwardly and downwardly directed portions connected by a longitudinal portion, a claw on each of said arms, a gravity engaging element having a pawl adapted to engage the claw of the thread testing arm, said gravity element being adapted to retain the thread testing arm in contact with its threads, the said arm being adapted to move upon the failure of the thread to resist the same, until the claw disengages from the said pawl and means for reciprocating the longitudinal bar, whereby the thread testing arms will be caused to test a plurality of threads.

7. A thread testing device embodying a thread engaging element adapted to engage a sewing thread, and means whereby the thread engaging element will indicate an abnormal condition of the thread, such as a slack or broken thread, said thread engaging element being adapted to detect and indicate a defective condition in the several threads with which it engages, and means for periodically moving said thread engaging element to cause it to successively engage and test a plurality of sewing threads.

Signed at St. Gall, in the Canton of St. Gall, Switzerland, this 2nd day of June,

MORRIS SCHOENFELD. Witnesses:.

CAESAR LOEB, FRIEDR. STEINER.

Washington, D. C. 

